/*
 * OREKIT-X
 * Copyright 2002-2008 CS Communication & Systemes
 * 
 * Parts of this software package have been licensed to CS
 * Communication & Systemes (CS) under one or more contributor license
 * agreements.  See the NOTICE file distributed with this work for
 * additional information.
 *  
 * This is an experimental copy of OREKIT from www.orekit.org.
 * Please use the original OREKIT from orekit.org for normal work
 * unrelated to this research project.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License.  You
 * may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied.  See the License for the specific language governing
 * permissions and limitations under the License.
 */
package ore.propagation;

import ore.SpacecraftState;
import ore.errors.PropagationException;
import ore.time.AbsoluteDate;

/** 
 * This interface provides a way to propagate an orbit at any time.
 *
 * This interface is the simplest abstraction for orbit propagation.
 * It only allows propagation to a predefined date.
 * 
 * @author Luc Maisonobe
 * @author V&eacute;ronique Pommier-Maurussane
 */
public interface BasicPropagator
    extends java.io.Serializable
{
    /** 
     * Propagate towards a target date.
     * 
     * Simple propagators use only the target date as the
     * specification for computing the propagated state. More feature
     * rich propagators like the ones implemented the extended
     * interface {@link Propagator} can consider other information and
     * provide different operating modes or G-stop facilities to stop
     * at pinpointed events occurrences. In these cases, the target
     * date is only a hint, not a mandatory objective.
     *
     * @param target target date towards which orbit state should be propagated
     * @return propagated state
     * @exception PropagationException if state cannot be propagated
     */
    public SpacecraftState propagate(AbsoluteDate target) throws PropagationException;

}
